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authorJakub Jelinek <jakub@redhat.com>2007-07-31 13:33:18 +0000
committerJakub Jelinek <jakub@redhat.com>2007-07-31 13:33:18 +0000
commit32c075e1f01849e161724bbd400ba77244e482cc (patch)
tree5f083a3f352104f32bb6c902d57fa3f294bd8d4d /nptl/pthread_cond_wait.c
parentd6220e9ee38c1c9285221b023346201ec5f511b3 (diff)
.
Diffstat (limited to 'nptl/pthread_cond_wait.c')
-rw-r--r--nptl/pthread_cond_wait.c191
1 files changed, 0 insertions, 191 deletions
diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c
deleted file mode 100644
index f5f5cec5a8..0000000000
--- a/nptl/pthread_cond_wait.c
+++ /dev/null
@@ -1,191 +0,0 @@
-/* Copyright (C) 2003, 2004, 2006 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
-
-#include <endian.h>
-#include <errno.h>
-#include <sysdep.h>
-#include <lowlevellock.h>
-#include <pthread.h>
-#include <pthreadP.h>
-
-#include <shlib-compat.h>
-
-
-struct _condvar_cleanup_buffer
-{
- int oldtype;
- pthread_cond_t *cond;
- pthread_mutex_t *mutex;
- unsigned int bc_seq;
-};
-
-
-void
-__attribute__ ((visibility ("hidden")))
-__condvar_cleanup (void *arg)
-{
- struct _condvar_cleanup_buffer *cbuffer =
- (struct _condvar_cleanup_buffer *) arg;
- unsigned int destroying;
-
- /* We are going to modify shared data. */
- lll_mutex_lock (cbuffer->cond->__data.__lock);
-
- if (cbuffer->bc_seq == cbuffer->cond->__data.__broadcast_seq)
- {
- /* This thread is not waiting anymore. Adjust the sequence counters
- appropriately. We do not increment WAKEUP_SEQ if this would
- bump it over the value of TOTAL_SEQ. This can happen if a thread
- was woken and then canceled. */
- if (cbuffer->cond->__data.__wakeup_seq
- < cbuffer->cond->__data.__total_seq)
- {
- ++cbuffer->cond->__data.__wakeup_seq;
- ++cbuffer->cond->__data.__futex;
- }
- ++cbuffer->cond->__data.__woken_seq;
- }
-
- cbuffer->cond->__data.__nwaiters -= 1 << COND_CLOCK_BITS;
-
- /* If pthread_cond_destroy was called on this variable already,
- notify the pthread_cond_destroy caller all waiters have left
- and it can be successfully destroyed. */
- destroying = 0;
- if (cbuffer->cond->__data.__total_seq == -1ULL
- && cbuffer->cond->__data.__nwaiters < (1 << COND_CLOCK_BITS))
- {
- lll_futex_wake (&cbuffer->cond->__data.__nwaiters, 1);
- destroying = 1;
- }
-
- /* We are done. */
- lll_mutex_unlock (cbuffer->cond->__data.__lock);
-
- /* Wake everybody to make sure no condvar signal gets lost. */
- if (! destroying)
- lll_futex_wake (&cbuffer->cond->__data.__futex, INT_MAX);
-
- /* Get the mutex before returning unless asynchronous cancellation
- is in effect. */
- __pthread_mutex_cond_lock (cbuffer->mutex);
-}
-
-
-int
-__pthread_cond_wait (cond, mutex)
- pthread_cond_t *cond;
- pthread_mutex_t *mutex;
-{
- struct _pthread_cleanup_buffer buffer;
- struct _condvar_cleanup_buffer cbuffer;
- int err;
-
- /* Make sure we are along. */
- lll_mutex_lock (cond->__data.__lock);
-
- /* Now we can release the mutex. */
- err = __pthread_mutex_unlock_usercnt (mutex, 0);
- if (__builtin_expect (err, 0))
- {
- lll_mutex_unlock (cond->__data.__lock);
- return err;
- }
-
- /* We have one new user of the condvar. */
- ++cond->__data.__total_seq;
- ++cond->__data.__futex;
- cond->__data.__nwaiters += 1 << COND_CLOCK_BITS;
-
- /* Remember the mutex we are using here. If there is already a
- different address store this is a bad user bug. Do not store
- anything for pshared condvars. */
- if (cond->__data.__mutex != (void *) ~0l)
- cond->__data.__mutex = mutex;
-
- /* Prepare structure passed to cancellation handler. */
- cbuffer.cond = cond;
- cbuffer.mutex = mutex;
-
- /* Before we block we enable cancellation. Therefore we have to
- install a cancellation handler. */
- __pthread_cleanup_push (&buffer, __condvar_cleanup, &cbuffer);
-
- /* The current values of the wakeup counter. The "woken" counter
- must exceed this value. */
- unsigned long long int val;
- unsigned long long int seq;
- val = seq = cond->__data.__wakeup_seq;
- /* Remember the broadcast counter. */
- cbuffer.bc_seq = cond->__data.__broadcast_seq;
-
- do
- {
- unsigned int futex_val = cond->__data.__futex;
-
- /* Prepare to wait. Release the condvar futex. */
- lll_mutex_unlock (cond->__data.__lock);
-
- /* Enable asynchronous cancellation. Required by the standard. */
- cbuffer.oldtype = __pthread_enable_asynccancel ();
-
- /* Wait until woken by signal or broadcast. */
- lll_futex_wait (&cond->__data.__futex, futex_val);
-
- /* Disable asynchronous cancellation. */
- __pthread_disable_asynccancel (cbuffer.oldtype);
-
- /* We are going to look at shared data again, so get the lock. */
- lll_mutex_lock (cond->__data.__lock);
-
- /* If a broadcast happened, we are done. */
- if (cbuffer.bc_seq != cond->__data.__broadcast_seq)
- goto bc_out;
-
- /* Check whether we are eligible for wakeup. */
- val = cond->__data.__wakeup_seq;
- }
- while (val == seq || cond->__data.__woken_seq == val);
-
- /* Another thread woken up. */
- ++cond->__data.__woken_seq;
-
- bc_out:
-
- cond->__data.__nwaiters -= 1 << COND_CLOCK_BITS;
-
- /* If pthread_cond_destroy was called on this varaible already,
- notify the pthread_cond_destroy caller all waiters have left
- and it can be successfully destroyed. */
- if (cond->__data.__total_seq == -1ULL
- && cond->__data.__nwaiters < (1 << COND_CLOCK_BITS))
- lll_futex_wake (&cond->__data.__nwaiters, 1);
-
- /* We are done with the condvar. */
- lll_mutex_unlock (cond->__data.__lock);
-
- /* The cancellation handling is back to normal, remove the handler. */
- __pthread_cleanup_pop (&buffer, 0);
-
- /* Get the mutex before returning. */
- return __pthread_mutex_cond_lock (mutex);
-}
-
-versioned_symbol (libpthread, __pthread_cond_wait, pthread_cond_wait,
- GLIBC_2_3_2);